PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 1714561

Tumor angiogenesis.

G Tobelem
View original source ↗Export metadata ↓

Abstract

Angiogenesis requires the migration, differentiation and proliferation of endothelial cells. Tumor growth is angiogenesis-dependent and angiogenesis is directly or indirectly induced by the tumor. Induction of angiogenesis is, therefore, an important stage in carcinogenesis and in the development of metastasis. Numerous angiogenic factors have been identified, most of which are mitogenic for endothelial cells and only some of which are responsible for tube formation. Pharmacologic compounds such as heparin, heparin fragments and corticosteroids have been shown to be anti angiogenic substances. Recently two new inhibitors of angiogenesis, a cartilage-derived inhibitor and platelet factor 4 have been described.

Explore related subjects

Growth SubstancesHumansNeoplasmsNeovascularization, PathologicJournal ArticleReview

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

G Tobelem. 1990. Tumor angiogenesis.. https://pubmed.ncbi.nlm.nih.gov/1714561/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2006

[The life of human hair follicle revealed].

The human hair follicle is a unique appendage which results from epithelio-mesenchymal interactions initiated around the 3rd month of development. This appendage has a very complex structure, with a dermal compartment and an epithelial compartment. The dermal compartment comprises the connective tissue sheath and the dermal papilla, both of which are irrigated by microvessels. The epithelial compartment is made of highly replicating matrix cells giving rise to three concentrical domains, namely the outer root sheath, the inner root sheath and the hair shaft. The pigmentation unit, responsible for hair color, is made of fully active melanocytes located on top of the dermal papilla. Altogether a hair follicle contains more than 20 different cell types, engaged in different differentiation pathways and/or interacting with each other. This complex appendage has a unique behavior in mammals since, after a hair production phase, it involutes in place before entering a resting phase after which it renews itself under a cyclical but stochastic way, out of a double reservoir of pluripotent stem cells able to also regenerate epidermis. For yet unknown reasons, this well ordered process can be disturbed, provoking alopecia. The pigmentation unit also renews itself under a cyclical way, out of a melanocyte progenitor reservoir which progressively declines with time, provoking the hair whitening process. Finally, the shape of the hair shaft is programmed from the bulb. What makes this appendage unique and fascinating is its high degree of autonomy, its incredibly complex though stable structure, the number of different cell types interacting under an equilibrated way and its potential of regeneration. It represents a true paradigm of tissue homeostasis, exemplifying in a small living cylinder all the fundamental laws of cell-cell and tissue interactions. This life is revealed in this short synthesis.

Growth Substances↗
PubMed2006

Advances in the management of leg ulcers--the potential role of growth factors.

Venous ulcers are a major health problem because of the increased costs of the treatment and the refractory nature of the ulcers. The treatment cost is estimated to be around 1 billion dollars per year in the United States (US), and the average cost for one patient over a lifetime exceeds dollars 400,000. There has been an increasing trend in the use of growth factors in their management. Genetic engineering has revolutionised the research of wound healing, as the majority of recombinant growth factors are now available for in vitro and in vivo studies. Online searches of Medline, Pub Medical and Embase were carried out using the terms venous ulcers, leg ulcers, growth factors and growth hormone. The literature regarding the potential role of growth factors in the management of leg ulcers is reviewed. The important clinical studies are critically analysed with a view to appreciate the emerging therapies and the further research possibilities in the management of venous leg ulcers. Clinical results with the use of growth factors in non-healing wounds are encouraging. However, small sample sizes and inconsistent end points in different clinical studies have been the main hurdle in reaching a definite conclusion. Further research is needed to provide the definite evidence. Future developments may include different delivery methods for the growth factors, use of different combinations of growth factors administered simultaneously or, sequentially, bioengineered skin grafts and chemical induction of angiogenesis with the use of gene transfer techniques.

Growth Substances↗